Benefits of FreeForm

Rectangular Image
on Rectangular Sensor

Image quality improving inside sensor area, especially at the edges

Using FreeForm optics to increase image quality, across the board, by optimizing an image to better fit a rectangular shape sensor.
Image optimization in line with the rectangular sensor, concentrating image quality where it matters most.

better  image quality

reduced image quality

Red denotes image quality (MTF)
Higher intensity depicts to increased image quality

People’s heads at the edges look stretched

People’s heads at the edges look natural

Volume Deformation Correction for Wide Angle Cameras

FreeForm optics allows to correct volume distortion deformation while maintaining the same wide field of view and low optical distortion

SMIA-TV Distortion
and Waviness Correction

SMIA-TV distortion and waviness correction is needed in many applications to ensure objects appear without wavy artefacts

With FreeForm optics, straight lines stay straight, and the lack of waviness/SMIA-TV distortion allows the entire image to lie within the sensor area

Wavy artefacts due to the full image does not fit in the sensor 

Full image fits in the sensor with no wavy artefacts

Wavy artefacts due to the full image does not fit in the sensor 

Sensor area

Sensor area

Increased Resolution for Super Wide-Angle Cameras

With FreeForm optics, the image can be “stretched out” to cover a larger sensor area, occupying more pixels on the sensor

The familiar fisheye camera used in surveillance cameras suffers from significant distortion, compressing the image into a circle. This degrades the ability of computer vision to parse highly distorted, lower fidelity information.

As a result, it provides higher resolution of the dewarped image. 33% to 138% more pixels can be used, and this is especially useful where more information in the image us critical.

Alvarez Zoom Lens

Using Alvarez FreeForm lenses to accomplish optical zoom,  lenses move perpendicular to the optical axis on a micrometer scale

Continuous Zoom

Discrete Zoom

This is in contrast to lenses in traditional zoom systems that move parallel to the optical axis on a millimeter scale, resulting in a big protruding lens, or using multiple cameras to achieve discrete zoom.

Today’s phones require multiple cameras to achieve “zoom”. This results in a more complex imaging architecture, takes up more phone real estate, and accomplishes only discrete zoom (currently at 0.5x, 1x and 2x)

A single alvarez camera module could replace these multiple cameras, and additionally introduce continuous zoom a superior customer experience. Additionally, Alvarez zoom could be used to achieve much higher zoom factors, e.g. 5x and 10X, and could be paired with a second camera at 1X magnification to deliver a superior zoom experience (as described in the next slide)

Conventional optics

FreeForm optics

The tilted edge lenses need complex mechanical alignment, images from left and right tilted cameras require computer correction

Wide Panoramic Cameras Using Off-axis Systems

Three cameras usage to enable extremely wide fields of view

By introducing FreeForm elements for enhanced specifications in the main camera, and edge lenses with an off-axis design it is possible to obtain a panoramic camera with a wide FOV in a very small form factor with all types of distortion being corrected (keystone, optical, SMIA and others)

No need for computer correction; No loss of resolution due to image correction; Image looks natural

stitched image

stitched image

Targeted Depth of Field

Any regions of the scene or image can be addressed separately during design stage to ensure enhanced image quality or other characteristics

Optimized for long distance

Optimized for short distance

In this automotive example, the regions of interest are far-off traffic lights, cars right in front of and darting pedestrians or cyclists from the edges

FreeForm optics are able to accomplish this targeted performance within a desired area of the image

The vehicle looks as though it is almost aligned with the front wheel of the semi-truck

With a FreeForm lens, the semi-truck look “more natural”, the car on the right, is depicted as its actual distance

Keystone Distortion Correction

Keystone distortion appears when the object is projected on a planar surface under specific angle

It can be efficiently corrected by FreeForm off-axis cameras and provide natural appearance of objects, correct distance estimation, smaller size of industrial machines

A FreeForm, off-axis lens stack has an optical axis that is “bent”, coming in closer to the edge of the phone, directed by the FreeForm lenses eventually onto the middle of the sensor.

This allows the display to be closer to edge of the phone maximizing its size.

Off-axis Design for a Smaller Bezel

Front-facing cameras create a “bezel” – an edge that the display will not “cover” to accommodate light entering the lens stack

To maximum the size of the display, an off-axis camera

(whose optical axis is “shifted” can be used so that the light enters closer to the edge of the phone)

A regular lens stack has an optical axis going through the center of each lens.

This means the display has to be further away from the edge of the phone to accommodate the path of light hitting the sensor.